6-6a=3a-3b+1, 9a-3b=5
<span>4b - 8 =3a, 3a-4b=-8
</span>
9a-3b=5
(3a-4b=-8 )*(-3 )
9a -3b= 5
-9a+12b=+24
adding both equations
9b=29, b=29/9
3a=4b-8=4*29/9 -8=(4*29-8*9)/9 = 44/9
a=44/27
a-b=44/27 - 29/9=44/27 - 29*3/27=-43/27
this is a correct answer, unfortunately they do not have this choice, probably they made mistake somewhere. I even check the solution of equations by substitution values of a and b into equations
Answer:
I get it now.
Step-by-step explanation:
Answer:
Explicit formula is an = 64(-3/4)^(n-1).
Step-by-step explanation:
Looks like a geometric sequence with a negative common ratio.
-48/64 = - 3/4
36 / -48 = -3/4
Now -27/36 = -3/4 so I think there's a typo in the question. Its -27 not -17.
The required formula is 64(-3/4)^(n-1) .
Answer:
b. 6
Step-by-step explanation:
I'm not 100% sure if this is the answer but here was my thinking process:
1/4 of 24 is 6, and 6 + 3 is 9, so the brothers age is probably 9, and then 24-9 is 15, and the difference between 15 and 9 is 6. Once again I don't know if this is right or not, but either way I hope this helps!
Answer:
2
Step-by-step explanation: